Diazo sensitized papers have been used for making duplicate copies from originals by means of contact printing and development of the exposed diazo paper in an aqueous ammonia vapor atmosphere. Diazo sensitized films have been used as a medium for making microfilm or microfiche masters and duplicates thereof because of the low cost, the high resolution and the increased speed of operation. Increasing demands are made on the film developing process, especially as to the speed of developing, so as to enable an efficient and high volume production of diazo film copies from a master film.
In some of the prior methods and apparatus which have been utilized for developing diazo film, it has been thought necessary that the development take place at higher pressure and higher temperature conditions as represented by prior knowledge of the design of previous processes of this type.
Representative prior art which is directed to film processing includes U.S. Pat. No. 2,009,962 issued to W. Kurten on July 30, 1935, U.S. Pat. No. 2,761,364 issued to E. L. Cross on Sept. 4, 1956, U.S. Pat. No. 3,147,687 issued to J. G. B. Halden on Sept. 8, 1964, U.S. Pat. No. 3,364,833 issued to R. B. Mulvaney on Jan. 23, 1968, and U.S. Pat. No. 3,411,906 issued to J. W. Boone et al. on Nov. 19, 1968.
Additionally, U.S. Pat. No. 3,435,751 issued to R. C. Goodman et al. on Apr. 1, 1969, discloses two body portions, spring seals and upper and lower heating elements. U.S. Pat. No. 4,056,824 issued to K. Iiyama et al. on Nov. 1, 1977, shows upper and lower heating elements in the rollers and also a heating element control.
U.S. Pat. No. 4,068,249 issued to K. Degenhardt et al. on Jan. 10, 1978, discloses spring seals and two body portions, U.S. Pat. No. 4,099,868 issued to H. Schroter et al. on July 11, 1978, discloses an evaporator chamber and a developing chamber connected with a tubing element, U.S. Pat. No. 4,122,473, issued to S. Ernohazy on Oct. 24, 1978 discloses a device for eliminating gaseous developer residue waste in an ammonia type diazo copying machine, and U.S. Pat. No. 4,135,814 issued to H. Schroter et al. on Jan. 23, 1979, shows a vaporizer cavity and a developing chamber with thermal control means.
Further, U.S. Pat. No. 4,150,992 issued to J. W. Meadows et al. on Apr. 24, 1979 discloses a high speed, low temperature and pressure diazo film processing method which uses two body portions with heating elements and a heating control, and U.S. Pat. No. 4,255,037 issued to J. W. Meadows et al. on Mar. 10, 1981 discloses high speed, low temperature and pressure diazo processing apparatus which uses two body portions with heating elements and heating control.
U.S. Pat. No. 4,243,310 issued to P. E. Herborn on Jan. 6, 1981 discloses pre-heat and developing chambers along with thermal control means in the nature of a heat-resistant spacer element connecting the developing chamber and the ammonia separation chamber.
Still further, German Document Nos. DT2656901 and DE2659485 disclose developing units for Diazo copying with external evaporators.
The above patents disclose processing methods and apparatus which include a number of advantageous features, however, it is desirable to operate the processor at higher speeds and at temperatures which are lower than are required for certain types of film. Certain state of the art diazo film processors require about 15 minutes to attain operating temperatures and process approximately 1500 microfiche per hour in an environment where the temperature of the film is about 180.degree. F. Additionally, it is desirable that the injection method for introducing the aqueous ammonia into the atmosphere and vicinity of the developing chamber be such as to precisely and completely develop the film without defects or moisture spots on the film which may interfere with reading of the data which is present on the film.